1. Field
The invention is in the field of devices and methods for sensing and measuring the swelling and shrinking of a flexible member using sensor devices particularly as related to sexual arousal in human beings.
2. State of the Art
The sensing and measurement of sexual arousal in human beings has been attempted over the years by means which detect the swelling and color changes of parts of the male and female human body due to engorgement with blood in response to sexual arousal. Observations include the change in color and swelling of the walls of the vagina, swelling of the breasts, and expansion due to blood flow, or tumescence of the penis. Such observations are particularly useful in diagnosing sexual dysfunctional problems, particularly in males, for assessing arousal patterns to various stimuli such as for determining deviant sexual tendencies in males for law enforcement and probational purposes, and for behavior modification.
The prior apparatus and methods of determining male sexual arousal are primarily based on the enlargement in diameter of the penis in response to sexual arousal. Such changes in diameter are primarily measured using three types of devices; a mercury-in-rubber detector, an indium gallium detector, and a flexible metal detector. However, each of the three devices are resistant to size changes and thus require a certain amount of force to deform, or stretch which can skew the actual measurements.
The mercury-in-rubber and the indium-gallium detectors measure the circumference of the penis and comprise a closed-ended, flexible tubing filled with mercury, and indium-gallium fluid, respectively, with an electrically conductive wire attached to opposite ends thereof and formed into a loop. The mercury and the indium-gallium fluid are both electrically conductive with the resistance thereof determined by the length and cross-sectional area of the liquid in the tube. The loop is sized to snugly fit around the shaft, or body of the a penis while in a non-aroused, or flaccid state. As the penis enlarges in diameter during sexual arousal, the flexible tubing is stretched, with the inner diameter thereof becoming smaller, such that the cross-sectional area of the mercury or the indium gallium therein becomes smaller, the length thereof becomes longer, and the electrical resistance of the fluid increases. By using an ohm meter connected to the respective wires of the device, the change in electrical resistance of the indium gallium can be measured as an indication of the increase in the diameter of the penis. Such devices must be of the correct size for the particular penis and are calibrated using a stepped conical gauge. They are only accurate when the penis is very hard and erect. Such devices are used once then must be disposed of.
The third device for sensing changes in the diameter of the penis is the flexible metal detector, which uses an arcuate, spring-steel band having one or more resistors, or strain gauges attached to the middle thereof. Size changes are measured by changes in resistance of the strain gauge using an ohm meter. Such device must be sized and calibrated for each particular size penis in the flaccid state and estimated erect state using a stepped, conical calibration gauge prior to each use. Such device is prone to tampering and being stretched out of calibration during use. They are expensive such that they are normally disinfected and reused.
Sensor devices such as those having two or more parts, such as Hall effect devices and the magnets used therewith are known in various arts for measuring distances. Hall effect devices operate by means of a constant current being applied through a plate therein and which plate produces a voltage potential crosswise thereto, which can be measured by means of a volt meter, when a magnetic field is applied perpendicularly thereto. The stronger the magnetic field, or flux, and the more perpendicular such flux lines are to the plate, the higher the crosswise voltage. Thus, when the first part, or Hall effect device is mounted to a member and the second part, or magnet is mounted to a second member which moves relative to the first member, the relative angular displacement and/or distance therebetween can be estimated based on the Hall effect voltage produced by the Hall effect device. Such devices have been used extensively on machinery and on a more limited basis on the human body such as to monitor the cervical dilation of expectant mothers and for use in joint and muscle rehabilitation.
Devices to sense the frequency of respiration comprising elastic belts which fit around the chest and which have indium-gallium or mercury switches to indicate respiration rate are widely known. These devices, however, do not indicate the depth of respiration. Recently, a respiration belt which utilizes a rather complex Hall effect type device has been developed which also measures respiration rate.
The use of galvanic skin response methods has been used for lie detection for many years. It comprises measuring the electrical resistance of the skin at the surface thereof, which varies depending on the amount of perspiration thereon. When a person lies, the conductivity of the skin generally increases with a corresponding decrease in electrical resistance is resistance is measured using a very sensitive ohm meter type device.